15.4.2 ndb_mgmd — The MySQL Cluster Management Server Daemon

The management server is the process that reads the cluster
configuration file and distributes this information to all nodes
in the cluster that request it. It also maintains a log of
cluster activities. Management clients can connect to the
management server and check the cluster's status.

Instructs the management server as to which file it should
use for its configuration file. By default, the management
server looks for a file named
config.ini in the same directory as the
ndb_mgmd executable; otherwise the file
name and location must be specified explicitly.

The -f shortcut is available beginning with
MySQL Cluster 4.1.8. This option also can be given as
-c file_name,
but this shortcut is obsolete and should
not be used in new installations.

--daemon, -d

Command-Line Format

--daemon

Permitted Values

Type

boolean

Default

TRUE

Instructs ndb_mgmd to start as a daemon
process. This is the default behavior.

Shows extended information regarding the configuration of
the cluster. With this option on the command line the
ndb_mgmd process prints information about
the cluster setup including an extensive list of the cluster
configuration sections as well as parameters and their
values. Normally used together with the
--config-file (-f) option.

As of MySQL 4.1.5, it is no longer necessary to specify a
connectstring when starting the management server. However, if
you are using more than one management server, a connectstring
should be provided and each node in the cluster should specify
its node ID explicitly.

The following files are created or used by
ndb_mgmd in its starting directory. From
MySQL 4.1.5, the log and PID files are placed in the
DataDir as specified in the
config.ini configuration file. In the list
that follows, node_id is the unique
node identifier.

ndb_node_id_cluster.log
(was cluster.log in version 4.1.3) is
the cluster events log file. Examples of such events include
checkpoint startup and completion, node startup events, node
failures, and levels of memory usage. A complete listing of
cluster events with descriptions may be found in
Section 15.5, “Management of MySQL Cluster”.

When the size of the cluster log reaches one million bytes,
the file is renamed to
ndb_node_id_cluster.log.seq_id
(was
cluster.log.seq_id
in version 4.1.3) where seq_id is
the sequence number of the cluster log file. (For example:
If files with the sequence numbers 1, 2, and 3 already
exist, the next log file is named using the number
4.)

ndb_node_id_out.log
(was node1.out in version 4.1.3) is the
file used for stdout and
stderr when running the management server
as a daemon.

ndb_node_id.pid
(was
nodenode_id.pid
in version 4.1.3) is the process ID file used when running
the management server as a daemon.